Kanye West is leading arch-rival 50 Cent in a highly-publicized sales battle.

The Chicago rapper's third solo album "Graduation" is on pace to sell 575,000 to 700,000 units in its first week, while New York-based 50 Cent is projected to move 550,000 copies of his third solo set, "Curtis."

Sales tracker Neilsen Soundscan had "Graduation" outselling "Curtis" by a margin of 437,000 to 310,000 one day after their September 11 release.

Last month, 50 Cent - whose real name is Curtis Jackson - told the Associated Press that he would retire from solo recording if West outsold him. "I just don't view him as competition based on our previous sales histories," he said.

"Billboard" Magazine senior editor Jonathan Cohen says 50 Cent has been hampered by a series of underperforming singles, while Kanye West is having a "charmed" experience, despite a widely-circulated September 9 outburst at the MTV Awards after going home empty-handed.

"These tantrums he goes on, these outlandish comments he makes, they don't really hurt him," Cohen said. "If anything, they've got more people interested in what he's all about."

50 Cent may not be ready for the retirement home just yet - Cohen says he may stage a late-week sales rally. In addition, country star Kenny Chesney may play spoiler: his September 11 release "Just Who I Am: Poets and Pirates," is so far on pace to sell 400,000 to 550,000 copies.